While it is known that higher-point amplitudes in SYM theory (and certainly those in other, less “simple” field theories) can have significantly more complicated analytic structure, a general criterion for determining the locations of singularities of Feynman integrals was formulated over 60 years ago by Landau [1]}. Recently it has proven fruitful to explore general implications of the Landau equations and other classic work on discontinuities of amplitudes in the context of the modern amplitudes program; see for example [2]}, [3]}, [4]}, [5]}, [6]}, [7]}, [8]}, [9]}, [10]}.
